Engine shaft actuated locomotive valve gear of the suspended eccentric rod type



2,4 16,982 E GEAR S. D. DEKLE March 4, 1941.

ENGINE SHAFT ACTUATED LOCOMOTIVE VALV OF THE SUSPENDED ECCENTBIC RODTYPE Filed May 10. 1944 4 Sheets-Sheet l INVENTOR SWW/afl. E/rzf.

@La ATTORNEY March 4, 1947. 5, D, DEKLE 2,416,982

ENGINE SHAFT ACTUATED LocoMo'rIvE VALVE GEAR 0F THE SUSPENDED ECCENTRIGNon TYPE Filed. May 10. 1944 4 Sheets-Sheet 2 Z 4 6' 8 M Il( 75 zu una/a arroz/vf' Y March 4, 1947. s. D. DEKLE 2,416,982

ENGINE SHAFT ACTUATED LCOMTIVE VALVE GEAR OF THE SUSPENDED ECCENTRIC RODTYPE Filed May 10, 1944 4 Sheets-Sheet 3 J5 M fhtw/wea y 17 PVs/rfa l Furvr/:vn fg .56 7

r EI /W :n 6.9 l #14 Vfl Faxen/mvp 70 1,7/7?

INVENTOR.

March 4, 1947. s, D, DEKLE 2,416,982

ENGINE SHAFT ACTUATED LOCOMOTIVE VALVE GEAR 0F THE SUSPENDED ECCENTRIGROD TYPE Filed May 10, 1944 4 Sheets-Sheet 4 r2' VERSE M mi PatentedMar. 4,4 1947 UNITED STATES PATENT OFFICE ENGINE SHAFT ACTUATEDLOCOMOTIVE VALVE GEAR OF THE SUSPENDED 11 Claims. 1

This invention relates to valve gears and, more particularly, to suchfor operating a locomotive.

The principal object of my invention, generally considered. is toprovide a steam-engine valve gear of improved construction andoperation.

Another object of my invention is to provide a valve gear which requiresonly a small amount of lap to obtain perfect valve events, as comparedto the larger valve laps of other types of gear, thereby cutting downexcessive wearing of valves and bushings, especially when in runningcut-oil.

A further object of my invention is to provide a valve gear that gives agreater amount of starting `power when obtaining full valve travel byquickly opening the steam port at the beginning of the piston stroke anddelaying closing of the exhaust port when the piston is nearingcompletion of its stroke.

A still further object of my invention is to pro- 'vide a valve gear inwhich the wearing points are greatly reduced, as. by the elimination ofcombination levers and union links.

An additional object of my invention is to provide a light-weight gearwhich is readily accessible and which is provided with a self-aligningbushing in the back end of the combination eccentric blade, therebyeliminating side stress and strain to the blade. due to lateral motionin the driving wheels.

Another object of the valve gear is to satisfactorily allow for the falland rise of the engine frame when going around curves, by making thevalve gear eccentric rod ratio large, that is, sixteen to one.

Other objects and advantages of the invention, relating to theparticular arrangement and construction of various parts, will becomeapparent as the description proceeds.

Referring to the drawing illustrating my invention,

Figure l is a Side elevation of the forward parts of the running gear ofa steam locomotive, including one embodiment of my improved valve gear.

Figure 2 is a fragmentary plan of the gear and associated parts shown inFigure 1.

Figure 3 is a vertical sectional view on the line III- III of Figure l,in the direction of the arrows, the gear, however, being shown inneutral position, as illustrated diagrammatically in Figure 8.

Figure 4 is a diagrammatic illustration of the gear when the reversingmechanism is in full driver I2.

2 forward position and the main crank in its forward dead centerposition.

Figure 5 is a View corresponding to Figure 4, but showing the positionsof the parts when the main driver has turned 90 in moving forward.

Figure 6 is a view corresponding to Figure 5, but showing the positionsof the parts when said driver has turned another 90 forward.

Figure is a view corresponding to Figure 6, hut showing the positions ofthe parts when the driver has turned still another 90 in moving forward.

Figure 8 is a diagrammatic illustration of the gear when the reversingmechanism is in neutral or running cutoi position, the full linepositions of the gear otherwise corresponding with Figure 7, and thedotted line positions attempting to show the positions of the parts whenthe main driver is in the angular positions represented by Figures 4, 5and 6.

Figure 9 is a view corresponding to Figure 8, but showing the positionsof the parts when the reverse mechanism is positioned for full travelreverse operation.

Figure 10 is a valve ellipse or displacement curve for a valve gearembodying my invention.

Referring to the drawings in detail, like parts being designated by likereference characters, and first considering Figures 1, 2 and 3, it willbe seen that I have illustrated one embodiment of my invention asapplied to a steam locomotive having on each side, only one of which isi1- lustrated, a forward driving wheel I I and a main driving wheel I2.Said wheels are journaled with respect to a locomotive frame I3 carryinga cylinder I4 with a steam chest I5. In the cylinder reciprocates adriving piston I6 and in the steam chest is a piston valve Il,illustrated only in the diagrammatic views of Figures 4 to 9 inclusive.

The piston I6 has a rod I 8 connected to a cross head I9 slidable on aguide 2| and to which is pivoted a connecting rod 22, the other end ofwhich is pivoted to the main crank pin 23 of the An eccentric crank 24is attached to a preferably axial extension 25 on` the main crank pin 23and preferably set so that its free end trails the movement of the maincrank pin 90 when the drivers are moving forward.

To the free end of the eccentric crank is pivoted the eccentric rod orblade 26, the forward or free end of which is, in turn, pivotallycarried by radius arms 21 and 28. The upper ends of the radius arms areconnected to intermediate portions of a reversing member or yoke 29, asby pivot pins 3| and 32, respectively, as shown most clearly in Figure3.

The reverse yoke 29 is part of the reversing mechanism for the gear. Itsupper portion is bifurcated to straddle the forward end of a reach rod33 and it is connected thereto by pivot pin 34.

The lower portion of the yoke 29 is also bifurcated and straddies a linkblock 35 which is slidable in an arcuate link or segment 35, said blockbeing connected to the yoke 29 by a pivot pin 31. The link 36 is mountedon the top of a gear frame 39, in turn carried by the main locomotiveframe I3. The lower bifurcated portions of the yoke 29 are each, inturn, bifurcated and straddle outer and inner elements 39 and 4I of theframe 38, and their lower ends carry generally rectangular blocks 42 and43 by means of pivot pins 44 and 45, said blocks being adapted toreciprocate vertically with respect to said frame 38 as the yoke ismoved by the reach rod 33.

The rise and fall of the lower ends of the reverse yoke is accounted forby the fact that the link slot 46 in which the block 35 moves has aradius of curvature (in the embodiment illustrated 3714") which islonger than the distance between the block 35 and the line passingthrough the axes of the pivot pins 44 and 45 (in the embodimentillustrated 26") This reciprocation movement is provided to insure thedesired sequence of valve events. In the embodiment illustrated theseblocks reciprocate of an inch, thereby allowing the reverse yoke to givethe correct radius through the radius arms to the front end of theeccentric rod or blade.

The gear frame 38 also carries a bell crank 41 comprising an elongatedhub portion 48 mounted between the elements 39 and 4I of the gear frame38 as on pivot pin 49. From the hub 48 projects an arm i in a generallyforward, horizontal direction and the forward end of which is straddledby a transmission link 52 to which it is connected as by means ofpivot'pin 53.

The lower end of the transmission link is also bifurcated and straddlesa portion of the eccentric rod 26 intermediate the ends but near theconnection with the radius arms 21 and 28, being connected thereto as bymeans of pivot pin 54.

The other bell crank arm 55 depends from the hub 43 and is desirablybifurcated, straddles, and is connected to the rear end of, a valve rod56, as by pivot pin 51. The front end of the valve rod is connected tothe valve cross head and valve stem 53 by means of pivot pin 59.

The reverse yoke 29 is operated to vary the cutoff provided by the gearand for the reversal of the direction of travel, as desired, by thereach rod 33, the rear end of which is connected to the outer crank 6Iof a reversing shaft 62, as by means of pivot pin 63, and the innercrank 64 of which is connected to the front end of reversing shaft 65,as by pivot pin 66. The reversing shaft is, in turn, manually operableas by means of reversing lever 61 to which it is connected, as by meansof pivot pin 68.

Referring now to the diagrammatic representation in Figure 4, it will beseen that, when the piston I6 is in forward dead-center position, therear end of the eccentric rod 26 is disposed 90 behind thecrank-connected end of the rod 22 so that, when the reversing mechanismis in the forward corner, as illustrated in Figure 1, the valve I1 isjust starting to admit steam, represented by the arrow 69 in Figure 4,from the live steam compartment 16 of the chest I5 through port 1| infront of the piston I6, the rear portion of said valve I1 having openedport I2 to exhaust and so as to avoid back pressure. This positioncorresponds with the point 13 on the valve ellipse of Figure 10.

Figure 5 shows the relative positions of the valve gear parts when thedrive wheel I2 has moved forward through an angle of During thismovement the piston I6 has moved approximately half of its stroke or toa point designated by the reference character 14 in Figure 10. At thesame time, the valve as shown has completely opened the port 1I and isstarting to close it. In other words, the valve, during this 90movement, has advanced from a slight opening of the steam port to beyondthe full opening thereof.

Figure 6 shows the position of the parts while the locomotive is movingforward, but with the crank in rear dead-center position. During thismovement from Figure 5 to Figure 6 cut-off has occurred, as designatedby the reference character 15 in Figure 10, followed by release,designated by reference character 16 in Figure 10, upon opening cf theport 1I to the exhaust chamber 11. Figure 6, therefore, corresponds withFigure 4, except that steam, represented by the arrow 18. is here justbeing admitted to the rear of the piston I6, with the forward end of thecylinder open to exhaust, the point on Figure 10 corresponding with thisposition being designated by the reference character 19.

Figure '7 shows Vthe succeeding position of the mechanism in which thedriver I2 has turned through another 90 in a forward direction, in whichposition the port 12 is fully open to admit steam back of the piston i6,exhaust taking place through port 1I to exhaust chamber 'I1 in front ofsaid piston, corresponding generally with position 8| on the valveellipse diagram of Figure 10. It will therefore be seen that Figure 7corresponds with Figure 5, except thatthe directions of motion of thevalve and piston are reversed and the position of `the valve is atapproximately the opposite end of the valve chamber.

Figure 8 combines the positions of Figures 4 to '7, inclusive, for thegear when the reverse mechanism is in neutral or what might bedesignated as running cut-off position, that is, with the gear set forminimum steam consumption or earliest possible cut-oit. This isrepresented by the thinnest ellipse, marked 82, in the diagram of Figurel0, the point 13 on said ellipse corresponding with thesetting when therear end of the eccentric `rod is positioned at 93 in forward travel.The point B4 on said ellipse 82 shows the cut-off which in theembodiment illustrated is at about 44.2% of the stroke. When the drivermoves through 90 to place the rear end of the eccentric rod at point 85,the position of thegear in Figure 10 is represented at 86 or during theexpansion of the steam aftercut-oi. The next point 81, representing theposition of the rear end of the eccentric rod after another movement of90, is shown in Figure l0 by the reference character 19, and the fullline position of the gear is represented on Figure lll-by the referencecharacter 86.

Figure 9 corresponds with Figure 8, except that the positions of theparts are shown for full reverse motion. Reference character 9 shows theposition of the rear end of the eccentric rod when the mechanism isotherwise as in Figure '1, and the characters 9|, 92 and 93,respectively, show the positions of the rear end of the eccentric rodwhen the mechanism is otherwise as in Figures 6. 5 and 4.

The points on Figure on the rearward motion valve ellipse 94 whichcorrespond, respectively, with points 9|, 92, 93 and 89 are 19, 95, 13and 96.

From the foregoing disclosure, it will be seen that I have provided avalve gear which operates solely from a single connection with the maincrank pin, the adjustment of the cut-ofi" and reversal thereof beingaccomplished by a yoke mounted on a frame and carrying the front end ofthe eccentric rod on radius arms, pivot friction being therebysubstituted, in almost all instances, by sliding friction, and all partsof the gear being conveniently accessible for lubrication andmaintenance.

The valve ellipse illustrated in Figure 10 shows that the events of portopening, cut-off, release and compression occur when the valve isrelatively remote from its dead center and, therefore, moving atrelatively great speed. This means that these events occur quitequickly, thereby improving the power output of the locomotive bypromptly admitting steam to the cyllnder and cutting it off withoutappreciable Wire drawing.

A consideration of Figure 1D will also show that the valve ellipses aresubstantially symmetrical, particularly for forward travel, that greateconomy in the use of steam may be accomplished in running cut-off andpositions adjacent thereto, and all of these advantages are obtainedwhen using a very small lap, which, in the embodiment illustrated, is 3Aof an inch, the exhaust lap being negative, that is, amounting to aclearance of 3/m of an inch.

The following table shows various features of one embodiment of my gear,having 28" cylinders, 7/32" lead, and 65/3H valve travel when movingforward:

connection therewith. Thus the fall and rise of the engine frame whengoing around curves is satisfactorily allowed for, as when the reverseyoke is positoned for full forward or reverse travel, the ratio inrelation to the main crank pin is approximately 16:1. In other words, avertical movement of the frame of even as much as one inch with respectto the Wheels, as upon rounding a curve, involves a relative movement ofthe transmission link 52 of only about 11g inch, so that thecorresponding valve movement is minimized, as contrasted with that inthe Brown Patent No. 1,076,406, for example, in which the ratio isapparently less than 7:1.

Although preferred embodiment of my invention has been disclosed, itwill be understood that modifications may be made within the spirit andscope of the appended claims.

I claim:

l. In a steam-engine valve gear, in combination with a frame, a. maincrank pin and a valve, an eccentric rod, one end of which is pivotedwith respect to a point substantially 90 out of phase, but movable withsaid crank pin, reversing mechanism to which the other end of said rodis pivoted to cause it to swing in an arc about a center determined bythe setting of said mechanism, said mechanism comprising a reverse yokecarrying a block slidable in a link fixed to the top of said frame, saidyoke having normally depending end portions carrying blocks verticallyreciprocable in said frame, radius arms the upper ends of which arepivotally carried by intermediate portions of said yoke and the lowerends of which are pivotally connected to the free end of said eccentricrod, a bell crank lever pivoted to said frame, a transmission linkconnecting one arm of said lever to an intermediate portion of saideccentric rod, and a valve rod con- The above data were obtained with agear having 28" stroke, l2" eccentric crank radius, and 37%" linkradius. The length between end pivots of the gear parts were: eccentricrod. 79%"; transmission link, 325%@ arm of bell crank to whichconnected, 81/ valve rod, 6335"; arm of bell crank to which connected,11%'2 radius arms, 32"; reverse yoke, S31/21; distance from radius armsconnecting points: (l) to link block, 10"; (2) to yoke blocks, 16",

The distance on the eccentric rod between the points of connection withthe transmission link and with the radius arms was 4%". This means thatsaid distance is about, but less than, 11g of the distance from thetransmission link connecco necting another arm of said lever to saidvalve,

to operate the latter.

2. In a steam-engine valve gear, in combination with a gear frame, amain crank pin and a valve, an eccentric crank secured to said pin andwith its free end trailing it 90 in forward motion, an eccentric rod,one end of which is pivoted to said free crank end, reversing mechanismcomprising an arcuate link fixed to said frame, a reversing member, ablock carried thereby and slidable in said link, means for moving saidmember, a link movably supporting the other end of said rod from a partof said reversing member below said block, a bell crank lever, pivotedto said frame, a transmission link contion with the eccentric rod to theeccentric crank necting one arm of said lever to an intermediate portionof said eccentric rod, and a valve rod connecting another arm of saidlever to said valve, to operate the latter.

3. In a steam-engine valve gear, in combination with a frame, a maincrank pin and a valve, an eccentric rod, one end of which is pivotedwith respect to a point substantially 90 out of phase but movable withsaid crank pin, a reverse yoke, a, link fixed to the top of said frame,a block car ried by said yoke and slidable in said link, said yokehaving normally depending end portions carrying blocks verticallyrcciprocable in said frame, radius arms, the upper ends of which arepivotally carried by intermediate portions of said yoke and the lowerends of which are pivotally connected to the free end of said eccentricrod, a bell crank lever pivcted to said frame, a transmission linkconnecting one end of said lever to an intermediate portion of saideccentric rod, and a valve rod connecting another arm ci said lever tosaid valve, to operate the latter.

4. In a steam-locomotive valve gear, in corn bination with a frame, amain crank pin and a valve, an eccentric rod, one end of which ispivoted with respect `to a point substantially 90 out of phase, butmovable with said crank pin, a reversing member having a lower endportion movably connected to said frame, and an upper end portion,operating means connected to said upper end portion, link meansconnecting the other end of said rod to said member intermediate saidupper and lower end portions, a bell crank lever pivoted to said frame,with one arm extending substantially horizontaal and another armdepending therebelow, a transmission link connecting the substantiallyhorizontal arm of said lever to an intermediate portion of saideccentric rod, and a valve rod connecting the depending arm of saidlever to said valve, to operate the latter, `the point of connection ofthe transmission link to the eccentric rod being close to the point ofsuspension of said rod from said reversing member link means, wherebythe valve movement due to the fall and rise of the frame with respect tothe main crank pin when the locomotive is going around curves isminimized and satisfactorily allowed for.

5, In a steam-engine valve in combination with a frame and a valve,valve-actuating mechanism, and reversing mechanism for said actuatingmechanism comprising a yoke, a link fixed to the top of said frame, ablock carried by said yoke and slidcble in said link, said yoke havingnormally depending and portions carrying blocks vertically reciprocablein said frame, and radius arms to said actuating mechanism, carried byintermediate portions of saitl yoke.

6. In a steam-engine valve gear, actuating mechanism for the valvecomprising linkage including an eccentric rod moved solely by connectionwith the main crank pin and supported on a frame intermediate said pinand valve, and a reverse yoke carrying a block slidable in a link xed tothe top of said frame, said yoke having normally depending end portionscarrying blocks vertically reciprocabe in said frame, radius arms theupper ends ci which are pivotally carried by intermediate portions ofsaid yoke and the lower ends of which are pivotally connected to thefree end of said eccentric rod.

7. In a steam-engine valve gear, in combination with a gear frame, amain crank pin and a valve, an eccentric crank secured to said pin andwith its free end trailing it 99 in forward motion, an eccentric rod,one end of which is pivoted to said free crank end, a reverse yokecarrying a block slidable in a link fixed to the top of said frame, saidyoke having normally depending end portions carrying blocks verticallyreciprocabie in said frame, radius arms the upper ends of which arepivotally carried by intermediate portions or said yoke and the lowerends of which are pivotally connected to the free end of said eccentricrod, a bell crank lever pivotcd to said frame and l0 with one armextending substantially horizontal and another arm depending therebelow,a trans mission link with its lower end pivoted to said eccentric rodnear its front end and its upper end pivoted to the free end of saidsubstantially horizontal bell crank arm, and a valve rod with its rearend pivoted to the free end of said depending bell crank arm and itsfront end pivoted to said valve for operating it.

8. In a steam-locomotive valve gear, in combination with a frame, a maincrank pin and a valve, an eccentric rod, one end of which is pivotedwith respect to a point substantially 90 out of phase, ibut movable withsaid crank pin, a reversing member having an upper end portion to whichoperating means is connected, and bifurcations extending downwardiytherefrom, straddling portions of said frame, and with lower endportions movably connected `to said frame portions, links connectingportions of said member intermediate its upper and lower end portions tothe other end of said rod to cause it to swing in an arc about a centerdetermined by thc setting of said member, a bell crank lever pivoted tosaid frame, a transmission link connecting one arm of said lever to anintermediate portion of said eccentric rod, and a valve rod connectinganother arm of said lever to said valve, to operate the latter, thepoint of connection of yhe transmission link to the eccentric rod beingclose to the point of suspension of said rod from said reversing memberlinks, whereby the valve movement due to the fall and rise of the framewith respect to the main crank pin when the locomotive is going aroundcurves is satisfactorily minimized and allowed for.

9. In a steam-engine valve gear, actuating mechanism for the valvecomprising a frame, an arcuate link fixed to said frame, a reversingmember, a block carried thereby and slidable in said linkl means formoving said member, an eccentric crank, an eccentric rod coupled theretoat one end, a link movably supporting the other end of said rod from apart of said reversing member below said carried block, and meansoperatively connecting an intermediate portion of said rod to saidvalve.

li). In a steam-engine valve gear, actuating mechanism for a valvecomprising aA frame, an arcuate link fixed to said frame, a reversingmember, a block carried thereby and slidablc in said link, a, portion ofsaid member normally depending below said block being mounted toreciprocate with respect to said frame as the member oscillates, meansfor moving said member, an

05 eccentric crank, an eccentric rod coupled thereto at one end, meansmovably supporting the other end of said rod from said reversing member,and means operatively connecting an intermediate portion of said rod tosaid valve.

11. In a steam-engine valve gear, actuating mechanism for the valvecomprising a frame, an arcuate link fixed to said frame, a reversingmember, a block carried thereby and slidahle in said link, means formoving said. member, an eccentric crank, an eccentric rod coupledthereto at one end, link means movably supporting the other end of saidrod from a part. of seid reversing momber beneath said Unk, a be2 crankpvoted to said frame, means connecting an intermediate pox tion of said350d to one arm of crank, and means operatively connecting the oher armof said cfank to said Valve.

SAMUEL D. DEKLE.

REFERENCES CITED The following reforme-251 :Jo of record 1u the le ofthis patent:

Number UNITED STATES PATENTS Name Date Brown Oct. 21, 1913 Snider Juy18, 1916 Trent Oct. 13, 1931 Brown Sept, 3, 1914 Talhert, Jan. 18, 1916Harris Mar. 22, 1927

